Theory of Operation

Flow switches are comprised of two main assemblies: the housing and the shuttle assembly. As liquid flow enters the flow switch, it passes through an orifice between the inlet and outlet ports.

When the flow reaches the switch's set point, a magnet shuttle overcomes the downward force of a return spring and actuates a hermetically sealed SPDT reed switch element inside the bonnet stem. As the flow decreases, the spring overcomes the lifting forced created by the liquid and deactivates the switch.